Sigid Hariyadi

The Trophic Status of the Lubuk Lampam Floodplain in South Sumatera, Indonesia

The Lubuk Lampam floodplain’s ecosystem i s naturally affected by the fluctuation of the water surface. This ecosystem also receives anthropogenic substances such as nutrient s and other chemicals , especially from the oil palm plantation and its industrial processing activities . The main objective of this research was to determine the trophic status of the floodplain using the trophic level index (TLI) and Carlson’s trophic state index (TSI). The water quality and the fish samples were collected and analy z ed from 7 stations representing various types of floodplain habitat. The results showed that the trophic status of Lubuk Lampam was hypereutrophic (very nutrient-rich) . This was also supported by the high increase of the body weight (“b” value more than 3) and the high gonadoso m atic index (GSI) of the studied fishes, i.e. Osteochilus vittatus 2.53-6.81% (male) and 3.00-15.86% (female); Helostoma temminckii 0.28-3.33% (male) and 1.30-10.43% (female); and Channa striata 0.33-0.59% (male) and 0.21-2.73% (female).

Manajemen Kualitas Air Dengan Teknologi Bioflok: Studi Kasus Pemeliharan Ikan Lele (Clarias Sp.)

Biofloc technology is one of the alternative to overcome the problem of water quality of cultivation environment which was adapted from conventional waste management techniques. The purpose of this study was to assess the young catfish culture by applying bioflocs of some consortium products, such as Bacillus megaterium (BM), Supernit (SP), Depok 165 (DP165), Kayajaga (KJ) compared to non biofloc application for improving the water quality. The results of this study and statistical test showed that the lowest concentration of TAN by probiotic KJ was about 2.56 mg L -1 , while the control was about 5.47 mg L -1 , and the consortium of bacteria gave effect to TAN value (p 0.05). The lowest concentration of nitrite by probiotic BM was about 0.065 mg L -1 , while the control was about 0.124 mg L -1 , and the consortium of bacteria gave effect to the nitrite value (p<0.05). The lowest concentration of nitrate by probiotic BM was about 1.203 mg L -1 , while the control was about 3.437 mg L -1 , and the consortium of bacteria gave effect to the nitrate value (p<0.05). Consortium of bacteria gave effect to the COD value (p<0.05), but all bioflocs treatments had an average value of COD higher than the control. The conclusion that the bioflocs aplication was able to improve the water quality shown by decreasing parameter values of TAN concentrations, ammonia, nitrite, and nitrate.